Please help. I can't figure out why my b7100 hst diesel won't crank over. I put in fresh fuel and new glow plugs but the only way she will crank over is a small squirt of starting fluid. Thanks so much for anyone's help.
She won't crank over.
- Thread starter pguerin1967
- Start date
Take the starter fluid and throw it away unless you have decided "My tractor does not start, let's destroy the engine". Do you have a WSM?? If not get one. Is the fuel solenoid moving? Does the engine crank over?
fried1765
Well-known member
Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
NO.....
"small squirt of starting fluid".....NEVER!!
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I'm kinda new to working on tractors and sorry no I don't have WSM. When I go to start it, it just blows black smoke out the stack. And after awhile it kills the battery.
85Hokie
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Lifetime Member
Equipment
BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Sounds as if your glow plugs are not "glowing"
tell me why YOU changed you glow plugs and the history UP TO this point of the tractor
tell me why YOU changed you glow plugs and the history UP TO this point of the tractor
This tractor was given to me by my wife's grandmother and it's been pretty abused. She said her uncle gave it to her and I figured it wasn't firing off because of bad glow plugs, but obviously that's not the case. She said those were the original glow plugs as far as she knew.
STOP-IT and get off that tractor before TPS takes it to foster care where you will only be allowed supervised visits until you finish owner training.
Now that you got rid of starting fluid you are killing the starter by long duration cranking. Let's regroup and start at square #1. While we talk put battery on trikle charge until it reaches 12.6 to 12.9 volts across posts. If battery can't be charged to at least 12.6 you should replace it. Thurley clean posts and BOTH ENDS of cables before reinstalling battery. If it reaches 12.6 but quickly discharges,have it load tested free at any auto parts store. If it passes load test but still rapidly discharges have starter tested. Ok,now let's get on same page with terminology to help comunictions while troubleshooting. Crank = engine being turned over by electric starter or pull rope. Start = going from not running to running. Slow crank = turning slower than normal. Slow to start = having to stay on start button/key position longer than normal. Even diesel engines in good condition can be difficult to start using weak battery. When engine fails to start right away,the continued cranking rapidly overheats starter and shorting's it's life. FINALLY we can get to your problem. The problem you describe often happens due to slow crank which we've already addressed. Secound most common is one or more glow plugs not heating. When attempting to start cold engine,touching each plug sometimes reveals not heating but ohm test or amp test is more accurate. IDK what ohms or amps your plugs are rated so hopefully someone with wsm will tell you. If after you make sure all the above is right and it still doesn't fire off normally we can dig deeper. Overfueling injectors cause black smoke but troubleshooting and remedy is usually best left to pros unless you have spare money prefer to skip tests and try replacement.WHOA! You posted that picture while these old sore fingers typed a response. I don't see a wire leading to glow plugs. If they aren't getting battery power (you must give them time to heat before turning engine over to start) that's almost certainly the problem.
fried1765
Well-known member
Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Yup.....
In your picture the glow plugs are certainly wired together, but there is no 12V power source TO them!
go to here and download your tractors WSM https://www.kubotabooks.com/AutoIndex/index.php?dir=Tractor Owners Manuals/
then download and print, then read it completely, now hit back back button and donate to the site for the knowledge you have gained.
then download and print, then read it completely, now hit back back button and donate to the site for the knowledge you have gained.
If you have trouble understanding diagrams for electric circuits to wire it back to origuinal,here's a shortcut to find out if lack of glow plug power is actually the problem. Put clips on each end of heavy wire,clip one end to any of three glow plugs and other to + battery post or cable post at starter. After 5 to 7 seconds try starting it. If it starts first unclip at battery end then at glow plug to reduce risk of shorting jumper wire. If it fails to kick off don't grind starter too long. Unclip at battery and let starter cool 5 minutes then repeat allowing 7 to 10 seconds before hitting start. If that solves your problem you can fuse jumper and wire it through a momentary switch instead of running circuit through widgets as originally. If you can't find switch with enough amp capacity,including a relay is still simpler than factory wiring.
whitetiger
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Kubota tech..BX2370, RCK60, B7100HST, RTV900 w plow, Ford 1100 FWA
The power wire is there, it comes up from under the #3 intake runner.
trial and error
Well-known member
Equipment
B7100dt manual trans. homemade FEL, 4 way hydraulic dozer blade
Sounds eerily like glow plugs are not warming or not being left to heat long enough. My b7100 takes a minimum of 10-20 seconds in the summer and significantly longer in the winter, the battery gets a float charger year round and with the above glow plug treatment it fires right off, if it doesn't I glow it longer, but with the good batteryand battery float charger it fires very quickly so long as it is glowed long enough. I could be off and it could be something major but as others have suggested start there
Runs With Scissors
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L2501 TLB , Grappel, Brush Hog, Box Blade, Ballast box, Forks, Tiller, PH digger
GreensvilleJay
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BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
easy glowplug test cheat.
measure battery voltage ( say it's 13.00 volts...)
connect DVM on glowplug wire.
turn ign switch to 'glowplug'
what does the DVM say after 5-10 seconds ??
I'd expect it to be 12 volts, then down to about 11.
This should indicate all 3 are working though the proper test is to totally disconnect them and measure each plug. typically they're 1 ohm each. If zero, it's shorted and bad, if infinite, it's open and bad.
measure battery voltage ( say it's 13.00 volts...)
connect DVM on glowplug wire.
turn ign switch to 'glowplug'
what does the DVM say after 5-10 seconds ??
I'd expect it to be 12 volts, then down to about 11.
This should indicate all 3 are working though the proper test is to totally disconnect them and measure each plug. typically they're 1 ohm each. If zero, it's shorted and bad, if infinite, it's open and bad.
So far the B7100 glow plug indicator has not been mentioned (seems to be a rather frequent problem).
trial and error
Well-known member
Equipment
B7100dt manual trans. homemade FEL, 4 way hydraulic dozer blade
Absolutely, it's very hard to see in the daylight, but if you put your hand over it, it should emit a glow